JP2009116227A - Color unevenness correction system and color unevenness correcting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color unevenness correction system etc., for a projector that can correct color unevenness with higher precision. <P>SOLUTION: The color unevenness correction system includes a measurement unit 340 provided between the projector and a projection object and measuring an image signal value of part of projection light projected by the projector to generate measurement information indicative of the image signal value, a support unit 330 supporting the measurement unit 340 movably, a driving unit 320 driving the support unit 330 to make the measurement unit 340 measure image signal values within a prescribed range of the projection light, a correction data generator generating color unevenness correction data on the basis of the measurement information, and a color unevenness correction unit correcting an image signal for projection on the basis of the color unevenness correction data so that color unevenness may be corrected. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a color unevenness correction system and a color unevenness correction method for a projector.

  Color unevenness (including luminance unevenness) may occur due to characteristics of the liquid crystal panel of the projector, deterioration of the optical system, and the like, and the projector needs to correct the color unevenness. For example, Japanese Patent Application Laid-Open No. 2004-228948 describes a method in which a projected image is captured by an imaging sensor and color unevenness is corrected based on imaging information.

  However, the imaging sensor has a characteristic that the center of the imaging region has the highest accuracy, and the accuracy decreases as the distance from the center increases. For this reason, in the case of a method using an imaging sensor, it is necessary to correct imaging information according to the position in the imaging region.

For example, Japanese Patent Application Laid-Open No. 2002-311500 describes a method in which a line sensor is provided on the back surface of an image projection surface on a screen and an image is corrected based on image data from the line sensor.
JP 2004-228948 A JP 2002-311500 A

  However, in the case of the method disclosed in Japanese Patent Laid-Open No. 2002-311500, the influence of the screen is affected, so that the color unevenness caused by the factor inside the projector cannot be corrected appropriately, and the screen is limited to the transmissive type. It will be.

  An object of the present invention is to provide a color unevenness correction system and a color unevenness correction method for a projector that can correct color unevenness with higher accuracy.

  In order to solve the above-described problem, a color unevenness correction system according to the present invention is provided between a projector and a projection target, measures an image signal value of a part of projection light projected by the projector, and detects the image. A measurement unit that generates measurement information indicating a signal value; a support unit that movably supports the measurement unit; and driving the support unit to obtain the image signal value in a predetermined range of the projection light. A driving unit that causes the image to be measured, a color unevenness correction data generation unit that generates color unevenness correction data based on the measurement information, and an image signal for projection so that the color unevenness is corrected based on the color unevenness correction data. And a color unevenness correction unit to be corrected.

  In addition, the color unevenness correction method according to the present invention projects a calibration image for performing calibration, is provided between the projector and the projection target, and is a part of the calibration image projected by the projector. The measurement information is generated while moving a measurement unit that measures the image signal value and generates measurement information indicating the image signal value, generates color unevenness correction data based on the measurement information, and corrects the color unevenness The image signal for projection is corrected based on the data so that the color unevenness is corrected.

  According to the present invention, the color unevenness correction system or the like allows an image signal value of a part of the projection light, not the entire projection light, while moving the measurement unit or the support unit provided between the projector and the projection target. Because it is less affected by the lens characteristics of the measuring unit and less affected by the projection object such as a screen, the image signal value can be measured more accurately, so the color can be measured with higher accuracy. Unevenness can be corrected.

  Further, the color unevenness correction system includes a measuring device including the measurement unit, the support unit, the driving unit, and a measurement side communication unit that communicates with a control device, and the color unevenness correction data generation unit, And a control-side communication unit that communicates with the measurement device and the projector, wherein the control-side communication unit transmits measurement control information to the measurement device and the color unevenness correction data. The color unevenness correction data is transmitted to the projector having the color unevenness correction unit, and the measurement side communication unit receives the measurement control information and transmits the measurement information to the control device. Then, the drive unit may drive the support unit so that the projection light in the predetermined range is measured based on the measurement control information.

  According to this, the color unevenness correction system or the like can use, for example, a PC (Personal Computer) or the like as a control device, and can apply different measurement devices depending on the projector model, so that the color unevenness can be more flexible. Can be corrected.

  Further, the projector projects a single color image a plurality of times while changing the gradation, and the color unevenness correction data generation unit generates color unevenness correction data for each gradation based on the measurement information of each gradation, The control-side communication unit may transmit color unevenness correction data for each gradation to the projector.

  According to this, since the color unevenness correction system or the like can generate color unevenness correction data for each gradation, the color unevenness can be corrected with higher accuracy.

  In addition, the control device includes an information generation unit that generates the measurement control information, the control-side communication unit receives projection area information related to a projection area of the projector from the projector, and the information generation unit Based on the projection area information, the measurement control information may be generated so that projection light in a range corresponding to the projection area is measured.

  According to this, since the color unevenness correction system or the like can measure the image signal value of the projection light in a range corresponding to the projection area of the projector, the color unevenness can be corrected with high accuracy and efficiency.

  The color unevenness correction data generation unit may determine an optimal value from the plurality of image signal values indicated by the measurement information and generate the color unevenness correction data using the optimal value as a reference value.

  According to this, a color unevenness correction system or the like can correct color unevenness with higher accuracy by generating color unevenness correction data using the optimum value as a reference value.

  Embodiments in which the present invention is applied to an uneven color correction system will be described below with reference to the drawings. In addition, the Example shown below does not limit the content of the invention described in the claim at all. In addition, all the configurations shown in the following embodiments are not necessarily essential as means for solving the invention described in the claims.

  FIG. 1 is a diagram illustrating a usage state of the color unevenness correction system in the present embodiment. The uneven color correction system includes a projector 100 that projects an image 30 on a screen 20, a PC 200 that functions as a control device, and a measurement device 300.

  The measuring apparatus 300 is provided between the projector 100 and the screen 20 which is a kind of projection object. The measuring apparatus 300 includes a horizontal bar-shaped support unit 330 that can move in the vertical direction, a vertical bar-shaped support unit 330 that can move in the horizontal direction, and a measurement unit that is provided at the intersection of the support units 330. 340 is included.

  The measurement apparatus 300 drives the support unit 330 to measure a part of the image signal value (for example, XYZ value) of the projection light projected by the projector 100 while changing the position of the measurement unit 340. The PC 200 generates color unevenness correction data based on the measurement information. The projector 100 corrects the color unevenness based on the color unevenness correction data.

  Next, functional blocks of projector 100 having such a function will be described. FIG. 2 is a functional block diagram of the projector 100 in this embodiment. The projector 100 includes a projector-side communication unit 110 that communicates with the PC 200, a storage unit 120 that stores various data, an image generation unit 130, a correction unit 140 that includes a color unevenness correction unit 142, and a projection unit 190. It consists of

  The storage unit 120 also includes calibration data 121 (for example, image data) for performing calibration, and color unevenness correction data 122 (for example, VT data indicating the relationship between drive voltage and transmittance for each pixel of the liquid crystal panel. Etc.) are stored.

  Next, functional blocks of the PC 200 will be described. FIG. 3 is a functional block diagram of the PC 200 in the present embodiment. The PC 200 includes a PC-side communication unit 210 that communicates with the projector 100 and the measurement apparatus 300, a storage unit 220 that stores various data, an information generation unit 230 that generates various information, and an uneven color correction data generation unit 240. And an operation unit 290.

  The storage unit 220 also includes measurement information 221 from the measurement apparatus 300, color unevenness correction data 222 generated by the color unevenness correction data generation unit 240, and a display area of the liquid crystal panel of the projector 100 (for example, horizontal and vertical directions). Projection area information 223 indicating the number of pixels), measurement area information 224 indicating the measurement area of the measuring apparatus 300 (for example, a movable range in the horizontal direction and the vertical direction, etc.), and the like are stored.

  Next, functional blocks of the measuring apparatus 300 will be described. FIG. 4 is a functional block diagram of the measuring apparatus 300 in the present embodiment. The measurement apparatus 300 includes a measurement-side communication unit 310 that communicates with the PC 200, a measurement unit 340, a support unit 330 that supports the measurement unit 340, and a drive unit 320 that moves the support unit 330.

  Note that these units may be implemented using, for example, the following hardware. For example, the projector-side communication unit 110, the PC-side communication unit 210, and the measurement-side communication unit 310 are USB communication units and wireless communication units, the storage unit 120 is a RAM, the image generation unit 130, and the correction unit 140 is image processing. A circuit, a projection unit 190 as a lamp, a liquid crystal driving circuit, a liquid crystal panel, a projection lens, etc., a storage unit 220 as an HDD, an information generation unit 230, a color unevenness correction data generation unit 240, a driving unit 320 as a CPU, etc. A gear, a motor, or the like may be employed as the support unit 330, and a color meter, a colorimeter, an illuminometer, or the like may be employed as the measurement unit 340.

  In the present embodiment, the measurement apparatus 300 can measure any image signal value (XYZ value in the present embodiment) of a part (predetermined range) of the projection light projected by the projector 100 in any measurable range. XYZ values are measured at the measurement position.

  FIG. 5 is a schematic diagram showing measurement positions in the present example. Moreover, FIG. 6 is a figure which shows the measurement position and measured value in a present Example. For example, in this embodiment, as shown in FIG. 1, the measurable range (screen 20) has an aspect ratio of 4: 3 and can be moved in 32 steps in the horizontal direction (x direction) and in 24 steps in the vertical direction. The aspect ratio of the display area of the liquid crystal panel of the projector 100 is 16: 9, and the display area is 1920 pixels in the horizontal direction and 1080 pixels in the vertical direction.

  In this case, as shown in FIG. 1, the user projects an image 30 using the projector 100 in such a way that a gap is formed on each of the upper and lower sides of the screen 20. For this reason, the measuring apparatus 300 can actually measure the x value in the range of 0 to 31 and the y value in the range of 0 to 23. However, in FIG. Is not measured because it is a non-display portion of the image 30. In the case of the number of pixels in the display area, one square shown in FIG. 6 corresponds to 60 pixels in the horizontal direction and 45 pixels in the vertical direction.

  Next, the color unevenness correction procedure using the measuring apparatus 300 and the like will be described in more detail. FIG. 7 is a flowchart showing a procedure for correcting color unevenness in the present embodiment. For example, when the user operates the operation unit 290 to give a calibration instruction, the PC 200 starts calibration for correcting uneven color. First, the information generation unit 230 generates projection control information by designating a gradation from the gradation range to be measured, and the PC side communication unit 210 transmits the projection control information to the projector 100 (step C1). .

  The projector side communication unit 110 receives the projection control information (step P1). The image generation unit 130 generates a white monochrome image (calibration image, that is, an image for performing calibration) based on the calibration data 121, and adjusts the gradation of the monochrome image based on the projection control information. The single-color image thus generated is generated, and the projection unit 190 projects the single-color image whose gradation has been adjusted (step P2).

  The information generation unit 230 determines a measurement target range (for example, x = 0 to 31, y = 3 to 20, etc.) based on the projection region information 223 and the measurement region information 224, and determines a measurement position ( For example, the position of x = 0, y = 3, etc.) is designated to generate measurement control information, and the PC side communication unit 210 transmits the measurement control information to the measurement apparatus 300 (step C2).

  The measurement side communication unit 310 receives the measurement control information (step S1). The drive unit 320 moves the support unit 330 so that the measurement unit 340 is positioned at the measurement position specified by the measurement control information, and transmits a control signal to the measurement unit 340 via the support unit 330 to perform measurement. The unit 340 is caused to measure the XYZ value at the measurement position of the monochrome image projected by the projector 100 (step S2).

  The measurement unit 340 measures the XYZ value at the measurement position and generates measurement information indicating the measurement position and the XYZ value, and the measurement-side communication unit 310 transmits the measurement information to the PC 200 (step S3). .

  The PC-side communication unit 210 receives the measurement information and stores it as the measurement information 221 in the storage unit 220 (step C3). The information generation unit 230 determines whether or not the measurement of the entire measurement target range has been completed (step C4). When the measurement of the entire range has not been completed, the PC 200 or the like repeatedly executes the processes from step C2 to C4 described above while changing the measurement position.

  On the other hand, when the measurement of the entire range is finished, it is determined whether or not the measurement of all the gradations to be measured is finished (step C5). When the measurement of all the gradations has not been completed, the PC 200 or the like repeatedly executes the above-described processing from steps C1 to C5 while changing the gradation.

  On the other hand, when the measurement of all the gradations is completed, the color unevenness correction data generation unit 240, based on the measurement information 221, the optimum value (for example, the value with the least color unevenness and the most ideal value) at each measured gradation. (A value close to or the like) is determined (step C6).

  Further, the color unevenness correction data generation unit 240 generates the color unevenness correction data 222 indicating the VT value for each measurement position (for each pixel in the display area of the projection unit 190) using the determined optimum value as a reference value. The communication unit 210 transmits the color unevenness correction data 222 to the projector 100 (step C7).

  The projector-side communication unit 110 receives the color unevenness correction data 222 and stores it as the color unevenness correction data 122 in the storage unit 120 (step P3). The color unevenness correction unit 142 corrects the color unevenness by adjusting the transmittance for each pixel of the liquid crystal panel of the projection unit 190 based on the color unevenness correction data 122 (step P4).

  As described above, according to the present embodiment, the color unevenness correction system moves the measurement unit 340 or the support unit 330 provided between the projector 100 and the screen 20 and moves the projector 100 instead of the entire projection light. By measuring the image signal value of a part of the projection light projected by the lens, it is less affected by the lens characteristics of the measurement unit 340 and is less affected by the projection target such as the screen 20, so that the image is more accurately displayed. Since the signal value can be measured, the color unevenness can be corrected with higher accuracy.

  According to the present embodiment, the color unevenness correction system uses a measuring device 300 (for example, a measuring device having a different measurable range) depending on the model of the projector 100 by using a PC as a control device. Color unevenness can be corrected more flexibly.

  Further, according to the present embodiment, the color unevenness correction system can generate the color unevenness correction data 122 and 222 for each gradation, so that the color unevenness can be corrected with higher accuracy. Further, according to this embodiment, the color unevenness correction system can measure the image signal value of the projection light in a range corresponding to the projection area of the projector 100, and thus corrects the color unevenness with high accuracy and efficiency. be able to.

  Further, according to the present embodiment, the color unevenness correction system can correct the color unevenness with higher accuracy by generating the color unevenness correction data 122 and 222 using the optimum value for each gradation as a reference value. . For example, in the case of the technique using the imaging unit, the measurement value at the center position is used as the reference value regardless of the actual measurement value. However, in the case of the technique of this embodiment, the optimum value from the actual measurement value is used. Since it is possible to determine the measurement value at a correct position, color unevenness can be corrected with higher accuracy.

  Also, the execution timing of the color unevenness correction of the present embodiment may be, for example, at the time of calibration before the presentation is performed, or at the time of inspection of the projector 100 or the like. In particular, when the projector 100 is inspected, observation of the image 30 is not hindered even if the support unit 330 and the measurement unit 340 are on the front surface of the screen 20. When the presentation is performed, the measurement apparatus 300 moves the measurement unit 340 to any one of the upper left, upper right, lower right, and lower left positions, thereby preventing the support unit 330 and the measurement unit 340 from observing the image 30. The occurrence of a situation can be prevented.

  In addition, application of this invention is not limited to the Example mentioned above, A various deformation | transformation is possible. For example, the image signal value measured by the measurement unit 340 is not limited to the XYZ value, and may be, for example, an RGB value, a YUV value, an illuminance value, a luminance value, or the like. Further, the measurement range and measurement unit of the measurement unit 340 are not limited to the above-described embodiments. For example, the measurement unit 340 may measure the image signal value of the projection light pixel by pixel. Further, the monochromatic image projected by the projector 100 is not limited to white, and for example, an arbitrary color that is not easily affected by a color such as green can be adopted.

  In the above-described embodiment, the PC 200 transmits projection control information to the projector 100. However, the PC 200 generates a single color image while changing the gradation, and directs the image information indicating the single color image to the projector 100. You may send it.

  Further, the measuring device may include a plurality of measuring units 340. FIG. 8 is an external view of a measuring apparatus 301 according to another embodiment. For example, two sets of the measurement unit 340 and the support unit 330 illustrated in FIG. 1 may be provided. Thereby, since measurement part 340-1 and 340-2 can measure simultaneously, measurement can be completed in a shorter time. Of course, three or more measuring units 340 may be provided.

  Moreover, the support part 330 is not limited to a rod shape, and is not essential. FIG. 9 is an external view of a measuring apparatus 302 according to another embodiment. For example, the drive unit 321 is configured in a planar shape and generates a magnetic force at a desired position. Further, the measuring unit 341 is provided with a magnet on the back surface (the surface in contact with the planar driving unit 321). According to such a configuration, the drive unit 321 can move the measurement unit 341 to an arbitrary position by magnetic force without using the support unit 330.

  Further, the method for correcting the color unevenness is not limited to the above-described embodiment, and various methods can be employed. For example, when the image signal is corrected using a three-dimensional lookup table in order to correct color unevenness, the color unevenness correction unit 142 uses the color unevenness correction data 122 to store the three-dimensional lookup table. It may be corrected.

  When the projector 100 or the measurement apparatus 300 to be applied is changed, the PC 200 receives the projection area information 223 indicating the display area of the projector 100 from the projector 100 or changes the measurement apparatus 300 from the measurement apparatus 300 when the change is made. Measurement area information 224 indicating the measurement area may be received. According to this, the color unevenness correction system can correct the color unevenness with high accuracy even when the projector 100 and the measuring apparatus 300 are changed.

  Further, the projection target is not limited to the screen 20, and may be a white board, a wall, or the like, for example. Further, the control device is not limited to the PC 200, and may be, for example, a remote controller, a mobile phone, a portable information terminal, or the like. Further, the projector 100 is not limited to a front projection type projector, and may be a rear projection type projector (for example, a rear projector, a projection television, or the like).

  The projector 100 is not limited to a liquid crystal projector, and may be a projector using a DMD (Digital Micromirror Device), for example. DMD is a trademark of Texas Instruments Incorporated. Further, the function of the projector 100 may be distributed and implemented in a plurality of devices (for example, a PC and a projector).

  In addition, the forms of the measurement unit 340, the drive unit 320, the color unevenness correction data generation unit 240, and the like are not limited to the forms distributed to the projector 100, the PC 200, and the measurement apparatus 300 as in the above-described embodiments. For example, the measurement apparatus may have the above-described PC function, and communication may be performed between the measurement apparatus and the projector 100.

It is a figure which shows the use condition of the color nonuniformity correction system in a present Example. It is a functional block diagram of the projector in a present Example. It is a functional block diagram of PC in a present Example. It is a functional block diagram of the measuring apparatus in a present Example. It is a schematic diagram which shows the measurement position in a present Example. It is a figure which shows the measurement position and measured value in a present Example. It is a flowchart which shows the color nonuniformity correction procedure in a present Example. It is an external view of the measuring apparatus in another Example. It is an external view of the measuring apparatus in another Example.

Explanation of symbols

  20 screen (projection object), 30 images, 100 projector, 110 projector side communication unit, 120, 220 storage unit, 121 calibration data, 122 color unevenness correction data, 130 image generation unit, 140 correction unit, 142 color unevenness correction , 190 projection unit, 200 PC (control device), 210 PC side communication unit, 221 measurement information, 222 color unevenness correction data, 223 projection region information, 224 measurement region information, 230 information generation unit, 240 color unevenness correction data generation Unit, 300 to 302 measuring device, 310 measuring side communication unit, 320 driving unit, 330 support unit, 340 measuring unit

Claims (6)

A measurement unit that is provided between the projector and the projection object and that measures the image signal value of a part of the projection light projected by the projector and generates measurement information indicating the image signal value;
A support unit that movably supports the measurement unit;
A drive unit that causes the measurement unit to measure the image signal value in a predetermined range of the projection light by driving the support unit;
Based on the measurement information, a color unevenness correction data generating unit that generates color unevenness correction data;
A color unevenness correction unit that corrects an image signal for projection so that the color unevenness is corrected based on the color unevenness correction data;
An uneven color correction system comprising: The color unevenness correction system according to claim 1,
A measurement device having the measurement unit, the support unit, the drive unit, and a measurement-side communication unit that communicates with a control device;
The control device including the color unevenness correction data generation unit, and a control-side communication unit that communicates with the measurement device and the projector;
Including
The control-side communication unit transmits measurement control information to the measurement device, receives the color unevenness correction data, and transmits the color unevenness correction data to the projector having the color unevenness correction unit.
The measurement side communication unit receives the measurement control information and transmits the measurement information to the control device,
The color unevenness correction system, wherein the drive unit drives the support unit so that the projection light in the predetermined range is measured based on the measurement control information. The uneven color correction system according to claim 2,
The projector projects a monochrome image multiple times while changing the gradation,
The uneven color correction data generation unit generates uneven color correction data for each gradation based on the measurement information of each gradation,
The control-side communication unit transmits color unevenness correction data for each gradation to the projector. The color unevenness correction system according to any one of claims 2 and 3,
The control device includes an information generation unit that generates the measurement control information,
The control-side communication unit receives projection area information related to the projection area of the projector from the projector,
The color unevenness correction system, wherein the information generation unit generates the measurement control information based on the projection area information so that projection light in a range corresponding to the projection area is measured. In the color unevenness correction system according to any one of claims 1 to 4,
The color unevenness correction data generation unit determines an optimum value from the plurality of image signal values indicated by the measurement information, and generates the color unevenness correction data using the optimum value as a reference value. Unevenness correction system. Project a calibration image for calibration,
While moving a measuring unit that is provided between the projector and the projection target and measures the image signal value of a part of the calibration image projected by the projector and generates measurement information indicating the image signal value Generating the measurement information;
Based on the measurement information, color unevenness correction data is generated,
A color unevenness correction method, comprising: correcting an image signal for projection based on the color unevenness correction data so that the color unevenness is corrected.

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